Connectors of a split type are sometimes used in multi-electrode connectors of a type having for example up to several tens of terminals. Such connectors are useful in preventing erroneous insertion of the metal terminals in the connector body.
One example of such a split connector has male and female frames which are provided with male and female connectors split into a plurality of sub-connectors each having a small number of metal terminals. The frames have a plurality of accommodating apertures which house these split male and female sub-connectors separately. Each sub-connector is inserted into an accommodating aperture of the corresponding frame, its front surface coming up against an abutment wall formed on the inside surface of the respective aperture, and its rear surface being latched by a resilient latching piece projecting on the inside surface of the aperture so that it is retained in the frame. Furthermore, the arrangement is such that a lever formed with an arc-shaped cam groove is pivotally supported on one of the frames, a follower pin projecting from the other frame engaging this cam groove, such that by turning the lever, the one frame is drawn to the other frame and the corresponding male and female sub-connectors are fitted together and connected in a single action.
Such split connectors generally accommodate the sub-connectors in the frame apertures with a fixed clearance in order to accommodate mispositioning within tolerance between corresponding pairs of sub-connectors. Meanwhile, in units in which a lever is used to couple the two frames as described above, lateral loading acts on the frame which is being drawn in, acting in a direction at right angles to the direction of approach to the companion frame. As a result, when a clearance is provided as described above, the sub-connector which is being drawn in will engage with its companion sub-connector in a tilted or stressed state due to the lateral movement, and the electrical contact is liable to lack reliability since, inter alia, the male and female metal terminals with which the sub-connectors are equipped may meet only partially.
Furthermore, as regards the structure in the portion where the resilient latching pieces engage the rear surfaces of sub-connector when it is accommodated in an aperture, in the past the unit has generally had a pair of resilient latching pieces placed in the central area in the length direction of the two corresponding edges of the sub-connector. Consequently, if a sub-connector being drawn in is made to engage while a lateral load is acting as described above, it will tilt as the companion sub-connector inclines, pivoting about the latching portions, and there is a similar risk that the electrical contact between the male and female metal terminals will not be secure.
Moreover, in connectors with a lever arrangement the male and female frames are coupled by turning the lever which is made of a synthetic resin plate, and it is preferable that the two frames can be temporarily assembled prior to the operation of turning the lever so that the holding hand is free and the turning operation can be performed smoothly. In the prior art this temporary assembly has been achieved by inserting a follower pin, which is on the frame being drawn in, into the leading end of a cam groove formed in the lever while resiliently deforming the said lever. However, the lever itself is liable to warping after being manufactured and the follower pin is subject to gradual plastic deformation as it is repeatedly inserted and removed so that the follower pin is eventually no longer able to fit into the cam groove properly, which means that the temporary assembly of the frames is not stable.
The present invention has been arrived at based on the above situation, and it aims to make corresponding male and female sub-connectors engage with each other in a direct line. This ensures that the male and female metal terminals connect with each other properly.